Nvidia has sued Samsung and Qualcomm for allegedly infringing seven of its patents related to GPUs, and is trying to block the sale of some Samsung products in the U.S.

The lawsuits open a new and unexpected front in the smartphone patent wars, which have already led to numerous court battles. In a blog post Thursday, Nvidia called it an “important day” for the company and said they are the first patent lawsuits it has initiated in its 21-year history.

Nvidia filed the complaints with the U.S. International Trade Commission (ITC) and at the U.S. District Court in Delaware. It has asked the ITC to block shipments of Galaxy phones and tablets that contain Qualcomm’s Adreno, ARM’s Mali and Imagination’s PowerVR graphics architectures.

“Without licensing Nvidia’s patented GPU technology, Samsung and Qualcomm have chosen to deploy our IP without proper compensation to us,” Nvidia said in the blog post.

Samsung declined to comment on the lawsuits, said spokeswoman Lauren Restuccia, and Qualcomm did not immediately reply to a request for comment.

“Instead of developing its own graphics processing technology, Samsung purchases and uses Qualcomm’s infringing processors and GPUs, as well as other processors and GPUs that infringe the claims of the asserted patents,” Nvidia said in its Delaware complaint.

Nvidia said it tried to negotiate a license for its patents with Samsung, and that Samsung “repeatedly said that this was mostly their suppliers’ problem.”

The GPU maker claims seven of its patents have been infringed.

“Those patents include our foundational invention, the GPU, which puts onto a single chip all the functions necessary to process graphics and light up screens; our invention of programmable shading, which allows non-experts to program sophisticated graphics; our invention of unified shaders, which allow every processing unit in the GPU to be used for different purposes; and our invention of multithreaded parallel processing in GPUs, which enables processing to occur concurrently on separate threads while accessing the same memory and other resources.”

In the ITU complaint, Nvidia says the accused Samsung products use processors that incorporate three GPU architectures—Qualcomm’s Adreno, ARM’s Mali and Imagination’s PowerVR.

“Adreno GPUs are used in Qualcomm’s processors and chipsets. Other processors and chipsets used in Samsung’s accused products, including Samsung’s Exynos processors, use Mali GPUs or PowerVR GPUs,” Nvidia says in its complaint.

“Products using any one of these three types of GPUs infringe the asserted patents,” it says.